Presently, power transmission and transformer equipment usually adopt porcelain hollow insulator. However, porcelain insulator is explosive with heavy weight and large volume. It is easy to be broken and requires regular cleaning up. This caused much inconvenience for installation and maintenance.
In order to overcome above insufficiencies of porcelain insulator, a compound and hollow insulator made of organic synthesis material appeared.
The current manufacturing technology mainly includes two: One is to use single petticoat mould for silicon sulfide rubber (RTV) at room temperature to cast petticoat body piece by piece on the special equipment; The other is to use liquid silicon rubber (LSR) and double-component injection pump to inject and form petticoat body at medium temperature (120° C). The shortcoming of these two technologies is that the resistance property for electric corrosion and aging of the product's external insulation are poor. Meanwhile, their technical and economical efficiency are also low.
The weather & aging resistance property and electric corrosion resistance property of high temperature silicon sulfide rubber are extremely good. However, since it is in solid state, high temperature and high pressure are needed for manufacturing. And the insulating tube of hollow insulator is hollow, which is extremely easy to be broken once bearing the pressure, especially under high temperature. Therefore, it has not been applied in manufacturing hollow insulator in HV power station.